B2553

DTC B2553 Backup Lamps Control Circuit High:

CIRCUIT DESCRIPTION
The backup lamp circuit is completed by the BCM when it receives a signal from the PCM that the vehicle is in reverse. The BCM momentarily grounds circuit 38, energizing the backup lamp relay.

CONDITIONS FOR SETTING THE DTC
^ The BCM detects a short to B+ in circuit 38 while attempting to ground circuit 38.
^ The BCM tests for a short to B+ in circuit 38 only when attempting to turn on the backup lamps. All conditions must be present for more than 0.15 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The BCM stores DTC B2553 in memory.
^ The BCM turns off its output to the backup lamp relay.

CONDITIONS FOR CLEARING THE DTC
^ When the ignition switch is cycled from off to on, the current DTC is cleared. If the fault is present at the next backup lamp activation, this DTC sets as current.
^ A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
^ Using a scan tool.

DIAGNOSTIC AIDS
^ The following conditions may cause an intermittent malfunction to occur:
- An intermittent short to B+ in circuit 38.
- The BCM is shorted to B+ internally.
- The backup lamp relay coil is shorted to B+ internally.
^ If the DTC is a history DTC, the problem may be intermittent. Try performing the tests shown while moving wiring and connectors, this can often cause the malfunction to reappear.
^ DTC P1626 will set in the Powertrain Control Module (PCM) when the ignition switch is on with the Body Control module (BCM) disconnected. When BCM diagnostics and repairs are completed, refer to Computers and Control Systems for additional information on PCM related DTCs. Computers and Control Systems

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
2. This step checks for a short to B+ in circuit 38.
3. This step determines whether circuit 38 has a short to B+ or the BCM is faulty.
6. This step checks BCM DTC B2553 and checks for BCM DTC B2553 to set again.